The Institute of Medicine (IOM) of the National Academies, in a report entitled “The Childhood Immunization Schedule and Safety: Stakeholder Concerns, Scientific Evidence, and Future Studies,” determined there were no major safety concerns associated with following the federal childhood immunization schedule. The IMO report is a comprehensive examination of the current federal immunization schedule. The federal immunization schedule is timed to protect children from 14 pathogens by immunizing them at the stages in their lives when they are most susceptible to the diseases.

The IOM report concluded that following the complete childhood immunization schedule is strongly associated with reducing vaccine-preventable diseases. The report provided an outline for conducting additional safety research on the federal immunization schedule should the need arise. The report was created at the request of HHS to address some parents’ concerns about the safety and frequency of the current childhood immunization schedule.

The report found that approximately 90 percent of American children receive most childhood vaccines when they begin kindergarten; however, some parents do not follow the immunization schedule. Critics of the federal immunization policies have called for studies comparing health outcomes among vaccinated and unvaccinated children and for research to determine if subgroups exist that are predisposed to experiencing harmful health effects from the vaccines.